gis: Merged revisions 6920-6989 via svnmerge from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/gis@6990 bcc190cf-cafb-0310-a4f2-bffc1f526a37

5 files changed, 166 insertions, 176 deletions

diff --git a/django/template/__init__.py b/django/template/__init__.py
index 9b1868cfce..750c48988d 100644
--- a/django/template/__init__.py
+++ b/django/template/__init__.py
@@ -154,15 +154,12 @@ class StringOrigin(Origin):
 
 class Template(object):
     def __init__(self, template_string, origin=None, name='<Unknown Template>'):
-        "Compilation stage"
         try:
             template_string = smart_unicode(template_string)
         except UnicodeDecodeError:
             raise TemplateEncodingError("Templates can only be constructed from unicode or UTF-8 strings.")
-        if settings.TEMPLATE_DEBUG and origin == None:
+        if settings.TEMPLATE_DEBUG and origin is None:
             origin = StringOrigin(template_string)
-            # Could do some crazy stack-frame stuff to record where this string
-            # came from...
         self.nodelist = compile_string(template_string, origin)
         self.name = name
 
@@ -177,13 +174,18 @@ class Template(object):
 
 def compile_string(template_string, origin):
     "Compiles template_string into NodeList ready for rendering"
-    lexer = lexer_factory(template_string, origin)
-    parser = parser_factory(lexer.tokenize())
+    if settings.TEMPLATE_DEBUG:
+        from debug import DebugLexer, DebugParser
+        lexer_class, parser_class = DebugLexer, DebugParser
+    else:
+        lexer_class, parser_class = Lexer, Parser
+    lexer = lexer_class(template_string, origin)
+    parser = parser_class(lexer.tokenize())
     return parser.parse()
 
 class Token(object):
     def __init__(self, token_type, contents):
-        "The token_type must be TOKEN_TEXT, TOKEN_VAR, TOKEN_BLOCK or TOKEN_COMMENT"
+        # token_type must be TOKEN_TEXT, TOKEN_VAR, TOKEN_BLOCK or TOKEN_COMMENT.
         self.token_type, self.contents = token_type, contents
 
     def __str__(self):
@@ -200,7 +202,7 @@ class Lexer(object):
         self.origin = origin
 
     def tokenize(self):
-        "Return a list of tokens from a given template_string"
+        "Return a list of tokens from a given template_string."
         in_tag = False
         result = []
         for bit in tag_re.split(self.template_string):
@@ -226,30 +228,6 @@ class Lexer(object):
             token = Token(TOKEN_TEXT, token_string)
         return token
 
-class DebugLexer(Lexer):
-    def __init__(self, template_string, origin):
-        super(DebugLexer, self).__init__(template_string, origin)
-
-    def tokenize(self):
-        "Return a list of tokens from a given template_string"
-        result, upto = [], 0
-        for match in tag_re.finditer(self.template_string):
-            start, end = match.span()
-            if start > upto:
-                result.append(self.create_token(self.template_string[upto:start], (upto, start), False))
-                upto = start
-            result.append(self.create_token(self.template_string[start:end], (start, end), True))
-            upto = end
-        last_bit = self.template_string[upto:]
-        if last_bit:
-            result.append(self.create_token(last_bit, (upto, upto + len(last_bit)), False))
-        return result
-
-    def create_token(self, token_string, source, in_tag):
-        token = super(DebugLexer, self).create_token(token_string, in_tag)
-        token.source = self.origin, source
-        return token
-
 class Parser(object):
     def __init__(self, tokens):
         self.tokens = tokens
@@ -319,17 +297,17 @@ class Parser(object):
     def exit_command(self):
         pass
 
-    def error(self, token, msg ):
+    def error(self, token, msg):
         return TemplateSyntaxError(msg)
 
     def empty_variable(self, token):
-        raise self.error( token, "Empty variable tag")
+        raise self.error(token, "Empty variable tag")
 
     def empty_block_tag(self, token):
-        raise self.error( token, "Empty block tag")
+        raise self.error(token, "Empty block tag")
 
     def invalid_block_tag(self, token, command):
-        raise self.error( token, "Invalid block tag: '%s'" % command)
+        raise self.error(token, "Invalid block tag: '%s'" % command)
 
     def unclosed_block_tag(self, parse_until):
         raise self.error(None, "Unclosed tags: %s " %  ', '.join(parse_until))
@@ -358,57 +336,7 @@ class Parser(object):
         if filter_name in self.filters:
             return self.filters[filter_name]
         else:
-            raise TemplateSyntaxError, "Invalid filter: '%s'" % filter_name
-
-class DebugParser(Parser):
-    def __init__(self, lexer):
-        super(DebugParser, self).__init__(lexer)
-        self.command_stack = []
-
-    def enter_command(self, command, token):
-        self.command_stack.append( (command, token.source) )
-
-    def exit_command(self):
-        self.command_stack.pop()
-
-    def error(self, token, msg):
-        return self.source_error(token.source, msg)
-
-    def source_error(self, source,msg):
-        e = TemplateSyntaxError(msg)
-        e.source = source
-        return e
-
-    def create_nodelist(self):
-        return DebugNodeList()
-
-    def create_variable_node(self, contents):
-        return DebugVariableNode(contents)
-
-    def extend_nodelist(self, nodelist, node, token):
-        node.source = token.source
-        super(DebugParser, self).extend_nodelist(nodelist, node, token)
-
-    def unclosed_block_tag(self, parse_until):
-        command, source = self.command_stack.pop()
-        msg = "Unclosed tag '%s'. Looking for one of: %s " % (command, ', '.join(parse_until))
-        raise self.source_error( source, msg)
-
-    def compile_function_error(self, token, e):
-        if not hasattr(e, 'source'):
-            e.source = token.source
-
-def lexer_factory(*args, **kwargs):
-    if settings.TEMPLATE_DEBUG:
-        return DebugLexer(*args, **kwargs)
-    else:
-        return Lexer(*args, **kwargs)
-
-def parser_factory(*args, **kwargs):
-    if settings.TEMPLATE_DEBUG:
-        return DebugParser(*args, **kwargs)
-    else:
-        return Parser(*args, **kwargs)
+            raise TemplateSyntaxError("Invalid filter: '%s'" % filter_name)
 
 class TokenParser(object):
     """
@@ -426,7 +354,7 @@ class TokenParser(object):
 
     def top(self):
         "Overload this method to do the actual parsing and return the result."
-        raise NotImplemented
+        raise NotImplementedError()
 
     def more(self):
         "Returns True if there is more stuff in the tag."
@@ -435,7 +363,7 @@ class TokenParser(object):
     def back(self):
         "Undoes the last microparser. Use this for lookahead and backtracking."
         if not len(self.backout):
-            raise TemplateSyntaxError, "back called without some previous parsing"
+            raise TemplateSyntaxError("back called without some previous parsing")
         self.pointer = self.backout.pop()
 
     def tag(self):
@@ -443,7 +371,7 @@ class TokenParser(object):
         subject = self.subject
         i = self.pointer
         if i >= len(subject):
-            raise TemplateSyntaxError, "expected another tag, found end of string: %s" % subject
+            raise TemplateSyntaxError("expected another tag, found end of string: %s" % subject)
         p = i
         while i < len(subject) and subject[i] not in (' ', '\t'):
             i += 1
@@ -459,14 +387,14 @@ class TokenParser(object):
         subject = self.subject
         i = self.pointer
         if i >= len(subject):
-            raise TemplateSyntaxError, "Searching for value. Expected another value but found end of string: %s" % subject
+            raise TemplateSyntaxError("Searching for value. Expected another value but found end of string: %s" % subject)
         if subject[i] in ('"', "'"):
             p = i
             i += 1
             while i < len(subject) and subject[i] != subject[p]:
                 i += 1
             if i >= len(subject):
-                raise TemplateSyntaxError, "Searching for value. Unexpected end of string in column %d: %s" % (i, subject)
+                raise TemplateSyntaxError("Searching for value. Unexpected end of string in column %d: %s" % (i, subject))
             i += 1
             res = subject[p:i]
             while i < len(subject) and subject[i] in (' ', '\t'):
@@ -483,7 +411,7 @@ class TokenParser(object):
                     while i < len(subject) and subject[i] != c:
                         i += 1
                     if i >= len(subject):
-                        raise TemplateSyntaxError, "Searching for value. Unexpected end of string in column %d: %s" % (i, subject)
+                        raise TemplateSyntaxError("Searching for value. Unexpected end of string in column %d: %s" % (i, subject))
                 i += 1
             s = subject[p:i]
             while i < len(subject) and subject[i] in (' ', '\t'):
@@ -542,8 +470,8 @@ class FilterExpression(object):
         for match in matches:
             start = match.start()
             if upto != start:
-                raise TemplateSyntaxError, "Could not parse some characters: %s|%s|%s"  % \
-                                           (token[:upto], token[upto:start], token[start:])
+                raise TemplateSyntaxError("Could not parse some characters: %s|%s|%s"  % \
+                                           (token[:upto], token[upto:start], token[start:]))
             if var == None:
                 var, constant, i18n_constant = match.group("var", "constant", "i18n_constant")
                 if i18n_constant:
@@ -552,9 +480,9 @@ class FilterExpression(object):
                     var = '"%s"' % constant.replace(r'\"', '"')
                 upto = match.end()
                 if var == None:
-                    raise TemplateSyntaxError, "Could not find variable at start of %s" % token
+                    raise TemplateSyntaxError("Could not find variable at start of %s" % token)
                 elif var.find(VARIABLE_ATTRIBUTE_SEPARATOR + '_') > -1 or var[0] == '_':
-                    raise TemplateSyntaxError, "Variables and attributes may not begin with underscores: '%s'" % var
+                    raise TemplateSyntaxError("Variables and attributes may not begin with underscores: '%s'" % var)
             else:
                 filter_name = match.group("filter_name")
                 args = []
@@ -570,7 +498,7 @@ class FilterExpression(object):
                 filters.append( (filter_func,args))
                 upto = match.end()
         if upto != len(token):
-            raise TemplateSyntaxError, "Could not parse the remainder: '%s' from '%s'" % (token[upto:], token)
+            raise TemplateSyntaxError("Could not parse the remainder: '%s' from '%s'" % (token[upto:], token))
         self.filters = filters
         self.var = Variable(var)
 
@@ -627,7 +555,7 @@ class FilterExpression(object):
                 provided.pop(0)
         except IndexError:
             # Not enough
-            raise TemplateSyntaxError, "%s requires %d arguments, %d provided" % (name, len(nondefs), plen)
+            raise TemplateSyntaxError("%s requires %d arguments, %d provided" % (name, len(nondefs), plen))
 
         # Defaults can be overridden.
         defaults = defaults and list(defaults) or []
@@ -636,7 +564,7 @@ class FilterExpression(object):
                 defaults.pop(0)
         except IndexError:
             # Too many.
-            raise TemplateSyntaxError, "%s requires %d arguments, %d provided" % (name, len(nondefs), plen)
+            raise TemplateSyntaxError("%s requires %d arguments, %d provided" % (name, len(nondefs), plen))
 
         return True
     args_check = staticmethod(args_check)
@@ -816,22 +744,6 @@ class NodeList(list):
     def render_node(self, node, context):
         return node.render(context)
 
-class DebugNodeList(NodeList):
-    def render_node(self, node, context):
-        try:
-            result = node.render(context)
-        except TemplateSyntaxError, e:
-            if not hasattr(e, 'source'):
-                e.source = node.source
-            raise
-        except Exception, e:
-            from sys import exc_info
-            wrapped = TemplateSyntaxError('Caught an exception while rendering: %s' % e)
-            wrapped.source = node.source
-            wrapped.exc_info = exc_info()
-            raise wrapped
-        return result
-
 class TextNode(Node):
     def __init__(self, s):
         self.s = s
@@ -861,21 +773,6 @@ class VariableNode(Node):
         else:
             return force_unicode(output)
 
-class DebugVariableNode(VariableNode):
-    def render(self, context):
-        try:
-            output = force_unicode(self.filter_expression.resolve(context))
-        except TemplateSyntaxError, e:
-            if not hasattr(e, 'source'):
-                e.source = self.source
-            raise
-        except UnicodeDecodeError:
-            return ''
-        if (context.autoescape and not isinstance(output, SafeData)) or isinstance(output, EscapeData):
-            return escape(output)
-        else:
-            return output
-
 def generic_tag_compiler(params, defaults, name, node_class, parser, token):
     "Returns a template.Node subclass."
     bits = token.split_contents()[1:]
@@ -887,7 +784,7 @@ def generic_tag_compiler(params, defaults, name, node_class, parser, token):
             message = "%s takes %s arguments" % (name, bmin)
         else:
             message = "%s takes between %s and %s arguments" % (name, bmin, bmax)
-        raise TemplateSyntaxError, message
+        raise TemplateSyntaxError(message)
     return node_class(bits)
 
 class Library(object):
@@ -913,7 +810,7 @@ class Library(object):
             self.tags[name] = compile_function
             return compile_function
         else:
-            raise InvalidTemplateLibrary, "Unsupported arguments to Library.tag: (%r, %r)", (name, compile_function)
+            raise InvalidTemplateLibrary("Unsupported arguments to Library.tag: (%r, %r)", (name, compile_function))
 
     def tag_function(self,func):
         self.tags[getattr(func, "_decorated_function", func).__name__] = func
@@ -937,7 +834,7 @@ class Library(object):
             self.filters[name] = filter_func
             return filter_func
         else:
-            raise InvalidTemplateLibrary, "Unsupported arguments to Library.filter: (%r, %r)", (name, filter_func)
+            raise InvalidTemplateLibrary("Unsupported arguments to Library.filter: (%r, %r)", (name, filter_func))
 
     def filter_function(self, func):
         self.filters[getattr(func, "_decorated_function", func).__name__] = func
@@ -966,7 +863,7 @@ class Library(object):
                 if params[0] == 'context':
                     params = params[1:]
                 else:
-                    raise TemplateSyntaxError, "Any tag function decorated with takes_context=True must have a first argument of 'context'"
+                    raise TemplateSyntaxError("Any tag function decorated with takes_context=True must have a first argument of 'context'")
 
             class InclusionNode(Node):
                 def __init__(self, vars_to_resolve):
@@ -1003,12 +900,12 @@ def get_library(module_name):
         try:
             mod = __import__(module_name, {}, {}, [''])
         except ImportError, e:
-            raise InvalidTemplateLibrary, "Could not load template library from %s, %s" % (module_name, e)
+            raise InvalidTemplateLibrary("Could not load template library from %s, %s" % (module_name, e))
         try:
             lib = mod.register
             libraries[module_name] = lib
         except AttributeError:
-            raise InvalidTemplateLibrary, "Template library %s does not have a variable named 'register'" % module_name
+            raise InvalidTemplateLibrary("Template library %s does not have a variable named 'register'" % module_name)
     return lib
 
 def add_to_builtins(module_name):
diff --git a/django/template/context.py b/django/template/context.py
index 0e41a26618..6ba53f340b 100644
--- a/django/template/context.py
+++ b/django/template/context.py
@@ -9,7 +9,6 @@ class ContextPopException(Exception):
 
 class Context(object):
     "A stack container for variable context"
-
     def __init__(self, dict_=None, autoescape=True):
         dict_ = dict_ or {}
         self.dicts = [dict_]
@@ -78,11 +77,11 @@ def get_standard_processors():
             try:
                 mod = __import__(module, {}, {}, [attr])
             except ImportError, e:
-                raise ImproperlyConfigured, 'Error importing request processor module %s: "%s"' % (module, e)
+                raise ImproperlyConfigured('Error importing request processor module %s: "%s"' % (module, e))
             try:
                 func = getattr(mod, attr)
             except AttributeError:
-                raise ImproperlyConfigured, 'Module "%s" does not define a "%s" callable request processor' % (module, attr)
+                raise ImproperlyConfigured('Module "%s" does not define a "%s" callable request processor' % (module, attr))
             processors.append(func)
         _standard_context_processors = tuple(processors)
     return _standard_context_processors
@@ -102,4 +101,3 @@ class RequestContext(Context):
             processors = tuple(processors)
         for processor in get_standard_processors() + processors:
             self.update(processor(request))
-
diff --git a/django/template/debug.py b/django/template/debug.py
new file mode 100644
index 0000000000..008059c28f
--- /dev/null
+++ b/django/template/debug.py
@@ -0,0 +1,97 @@
+from django.template import Lexer, Parser, tag_re, NodeList, VariableNode, TemplateSyntaxError
+from django.utils.encoding import force_unicode
+from django.utils.html import escape
+from django.utils.safestring import SafeData, EscapeData
+
+class DebugLexer(Lexer):
+    def __init__(self, template_string, origin):
+        super(DebugLexer, self).__init__(template_string, origin)
+
+    def tokenize(self):
+        "Return a list of tokens from a given template_string"
+        result, upto = [], 0
+        for match in tag_re.finditer(self.template_string):
+            start, end = match.span()
+            if start > upto:
+                result.append(self.create_token(self.template_string[upto:start], (upto, start), False))
+                upto = start
+            result.append(self.create_token(self.template_string[start:end], (start, end), True))
+            upto = end
+        last_bit = self.template_string[upto:]
+        if last_bit:
+            result.append(self.create_token(last_bit, (upto, upto + len(last_bit)), False))
+        return result
+
+    def create_token(self, token_string, source, in_tag):
+        token = super(DebugLexer, self).create_token(token_string, in_tag)
+        token.source = self.origin, source
+        return token
+
+class DebugParser(Parser):
+    def __init__(self, lexer):
+        super(DebugParser, self).__init__(lexer)
+        self.command_stack = []
+
+    def enter_command(self, command, token):
+        self.command_stack.append( (command, token.source) )
+
+    def exit_command(self):
+        self.command_stack.pop()
+
+    def error(self, token, msg):
+        return self.source_error(token.source, msg)
+
+    def source_error(self, source,msg):
+        e = TemplateSyntaxError(msg)
+        e.source = source
+        return e
+
+    def create_nodelist(self):
+        return DebugNodeList()
+
+    def create_variable_node(self, contents):
+        return DebugVariableNode(contents)
+
+    def extend_nodelist(self, nodelist, node, token):
+        node.source = token.source
+        super(DebugParser, self).extend_nodelist(nodelist, node, token)
+
+    def unclosed_block_tag(self, parse_until):
+        command, source = self.command_stack.pop()
+        msg = "Unclosed tag '%s'. Looking for one of: %s " % (command, ', '.join(parse_until))
+        raise self.source_error(source, msg)
+
+    def compile_function_error(self, token, e):
+        if not hasattr(e, 'source'):
+            e.source = token.source
+
+class DebugNodeList(NodeList):
+    def render_node(self, node, context):
+        try:
+            result = node.render(context)
+        except TemplateSyntaxError, e:
+            if not hasattr(e, 'source'):
+                e.source = node.source
+            raise
+        except Exception, e:
+            from sys import exc_info
+            wrapped = TemplateSyntaxError('Caught an exception while rendering: %s' % e)
+            wrapped.source = node.source
+            wrapped.exc_info = exc_info()
+            raise wrapped
+        return result
+
+class DebugVariableNode(VariableNode):
+    def render(self, context):
+        try:
+            output = force_unicode(self.filter_expression.resolve(context))
+        except TemplateSyntaxError, e:
+            if not hasattr(e, 'source'):
+                e.source = self.source
+            raise
+        except UnicodeDecodeError:
+            return ''
+        if (context.autoescape and not isinstance(output, SafeData)) or isinstance(output, EscapeData):
+            return escape(output)
+        else:
+            return output
diff --git a/django/template/defaultfilters.py b/django/template/defaultfilters.py
index 2f211dadb5..5cee0ab244 100644
--- a/django/template/defaultfilters.py
+++ b/django/template/defaultfilters.py
@@ -254,7 +254,7 @@ urlize.is_safe=True
 urlize.needs_autoescape = True
 urlize = stringfilter(urlize)
 
-def urlizetrunc(value, limit):
+def urlizetrunc(value, limit, autoescape=None):
     """
     Converts URLs into clickable links, truncating URLs to the given character
     limit, and adding 'rel=nofollow' attribute to discourage spamming.
@@ -262,8 +262,10 @@ def urlizetrunc(value, limit):
     Argument: Length to truncate URLs to.
     """
     from django.utils.html import urlize
-    return mark_safe(urlize(value, trim_url_limit=int(limit), nofollow=True))
+    return mark_safe(urlize(value, trim_url_limit=int(limit), nofollow=True,
+                            autoescape=autoescape))
 urlizetrunc.is_safe = True
+urlizetrunc.needs_autoescape = True
 urlizetrunc = stringfilter(urlizetrunc)
 
 def wordcount(value):
diff --git a/django/template/defaulttags.py b/django/template/defaulttags.py
index d91e30bbb5..726a37012b 100644
--- a/django/template/defaulttags.py
+++ b/django/template/defaulttags.py
@@ -84,19 +84,16 @@ class FirstOfNode(Node):
         return u''
 
 class ForNode(Node):
-    def __init__(self, loopvars, sequence, reversed, nodelist_loop):
+    def __init__(self, loopvars, sequence, is_reversed, nodelist_loop):
         self.loopvars, self.sequence = loopvars, sequence
-        self.reversed = reversed
+        self.is_reversed = is_reversed
         self.nodelist_loop = nodelist_loop
 
     def __repr__(self):
-        if self.reversed:
-            reversed = ' reversed'
-        else:
-            reversed = ''
+        reversed_text = self.is_reversed and ' reversed' or ''
         return "<For Node: for %s in %s, tail_len: %d%s>" % \
             (', '.join(self.loopvars), self.sequence, len(self.nodelist_loop),
-             reversed)
+             reversed_text)
 
     def __iter__(self):
         for node in self.nodelist_loop:
@@ -125,22 +122,23 @@ class ForNode(Node):
         if not hasattr(values, '__len__'):
             values = list(values)
         len_values = len(values)
-        if self.reversed:
+        if self.is_reversed:
             values = reversed(values)
         unpack = len(self.loopvars) > 1
+        # Create a forloop value in the context.  We'll update counters on each
+        # iteration just below.
+        loop_dict = context['forloop'] = {'parentloop': parentloop}
         for i, item in enumerate(values):
-            context['forloop'] = {
-                # Shortcuts for current loop iteration number.
-                'counter0': i,
-                'counter': i+1,
-                # Reverse counter iteration numbers.
-                'revcounter': len_values - i,
-                'revcounter0': len_values - i - 1,
-                # Boolean values designating first and last times through loop.
-                'first': (i == 0),
-                'last': (i == len_values - 1),
-                'parentloop': parentloop,
-            }
+            # Shortcuts for current loop iteration number.
+            loop_dict['counter0'] = i
+            loop_dict['counter'] = i+1
+            # Reverse counter iteration numbers.
+            loop_dict['revcounter'] = len_values - i
+            loop_dict['revcounter0'] = len_values - i - 1
+            # Boolean values designating first and last times through loop.
+            loop_dict['first'] = (i == 0)
+            loop_dict['last'] = (i == len_values - 1)
+
             if unpack:
                 # If there are multiple loop variables, unpack the item into
                 # them.
@@ -619,8 +617,8 @@ def do_for(parser, token):
         raise TemplateSyntaxError("'for' statements should have at least four"
                                   " words: %s" % token.contents)
 
-    reversed = bits[-1] == 'reversed'
-    in_index = reversed and -3 or -2
+    is_reversed = bits[-1] == 'reversed'
+    in_index = is_reversed and -3 or -2
     if bits[in_index] != 'in':
         raise TemplateSyntaxError("'for' statements should use the format"
                                   " 'for x in y': %s" % token.contents)
@@ -634,7 +632,7 @@ def do_for(parser, token):
     sequence = parser.compile_filter(bits[in_index+1])
     nodelist_loop = parser.parse(('endfor',))
     parser.delete_first_token()
-    return ForNode(loopvars, sequence, reversed, nodelist_loop)
+    return ForNode(loopvars, sequence, is_reversed, nodelist_loop)
 do_for = register.tag("for", do_for)
 
 def do_ifequal(parser, token, negate):
@@ -814,7 +812,7 @@ def ssi(parser, token):
     Outputs the contents of a given file into the page.
 
     Like a simple "include" tag, the ``ssi`` tag includes the contents
-    of another file -- which must be specified using an absolute page --
+    of another file -- which must be specified using an absolute path --
     in the current page::
 
         {% ssi /home/html/ljworld.com/includes/right_generic.html %}
@@ -926,20 +924,18 @@ def regroup(parser, token):
         {% regroup people|dictsort:"gender" by gender as grouped %}
 
     """
-    firstbits = token.contents.split(None, 3)
-    if len(firstbits) != 4:
+    bits = token.contents.split()
+    if len(bits) != 6:
         raise TemplateSyntaxError, "'regroup' tag takes five arguments"
-    target = parser.compile_filter(firstbits[1])
-    if firstbits[2] != 'by':
+    target = parser.compile_filter(bits[1])
+    if bits[2] != 'by':
         raise TemplateSyntaxError("second argument to 'regroup' tag must be 'by'")
-    lastbits_reversed = firstbits[3][::-1].split(None, 2)
-    if lastbits_reversed[1][::-1] != 'as':
+    if bits[4] != 'as':
         raise TemplateSyntaxError("next-to-last argument to 'regroup' tag must"
                                   " be 'as'")
 
-    expression = parser.compile_filter(lastbits_reversed[2][::-1])
-
-    var_name = lastbits_reversed[0][::-1]
+    expression = parser.compile_filter(bits[3])
+    var_name = bits[5]
     return RegroupNode(target, expression, var_name)
 regroup = register.tag(regroup)